Ivana Trump used a lavish St. Tropez bash to unveil her latest Italian beau, Marc Antonio Rota, for the Riviera social set.

Spies tell us that Trump and younger Rota — who’ve been quietly dating since last winter — “seemed madly in love” at the fete a few days ago where Rota, an Italian real-estate entrepreneur, serenaded Trump and her guests at the Pan Dei Palais by singing an Italian love song while wearing a white tux-and-tails.

“Tongues were wagging that Ivana brought him for all the world to see,” said a source. The party also featured “aquatic entertainment” in the form of synchronized swimmers, plus impersonators of Whitney Houston and Lady Gaga.

A friend of Ivana’s also sent a drag queen as a gift to “spice up the evening,” where the dress code stated, “Men: White Outfits — Ladies: Long Pastel Dresses.” Ivana served her own Ivana Blue Champagne for the bash and a cake was flown in from London.

But amidst all the fanfare, it was Rota who stole the show. “The highlight was Marc Antonio singing to Ivana,” said a guest.

There was even talk in the air of a possible marriage in the cards for Ivana, who’s walked down the aisle four times before — but a friend close to her told us, “They are not engaged, just enjoying their romance.”

Ivana, 63, has a thing for Italian men. Since her marriage to Donald Trump, all her boyfriends and two husbands have been Italian, from the late Count Roffredo Gaetani to Riccardo Mazzucchelli, Rossano Rubicondi and Antonio Zequila. Her fourth hubby, Rubicondi, whom she split with in 2008, was 23 years her junior.

Rota is hunky but “in his 50s,” leading a source at Trump’s party to quip, “at least he’s age-appropriate!”